1. Field of the Invention
Apparatuses consistent with the present invention relate to an image capturing module, and more particularly, to an image capturing module using a winding vibration type piezoelectric motor having a thin small volume and capable of performing a zoom or automatic focusing (AF) function in a digital camera.
2. Description of the Related Art
Currently, camera modules having an automatic focusing (AF) function or a zoom adjusting function implemented in mobile electronic devices, such as mobile phones, are being widely used. As the thickness of a camera module implemented in a mobile phone increases, the thickness of the mobile phone also increases. Thus, camera modules implemented in mobile phones may have a large volume and thickness.
In order to zoom or to automatically focus, a lens barrel supporting a lens may be moved along a guiding unit. As a driving unit for moving the lens barrel, a step motor or a piezoelectric motor is used. The step motor is driven by a step waveform (signal) based on an input pulse. Also, the step motor, which may be stepped, is controlled by a direct current source and driven by an electronic circuit, and has a rapid response in short-distance controlling.
However, in a step motor, since the size of an operating module increases due to increasing implementation of application parts, such as a reduction gear and connection parts, and an increasing size of the motor itself, and a cost of the motor increases due to the increasing implementation of the parts, a lens driving method using an ultrasonic motor such as a piezoelectric motor is widely used in camera modules employed in small digital cameras or mobile phones due to current light-weighted and minimized products.
Use of an ultrasonic motor is being gradually increased since an ultrasonic motor may be used to obtain high torque while being driven at low speed, may be manufactured in a structure different from that of a related art motor, and may not have a size limitation.
However, when a lens barrel driving device in a related art employing an inertia type piezoelectric motor is used, a piezoelectric motor driving unit needs to be disposed at a side of a lens module or a shutter module. Accordingly, a volume (width) of a side of the camera module increases.
Moreover, when a lens barrel driving device in a related art employing a winding vibration type piezoelectric motor is used, a driving unit may be disposed in a limited space, a lens module may be minutely controlled, and a lens and an image sensor may be maintained parallel to each other. However, in this case, the number of parts increases and an assembly tolerance of each part may be hardly reduced.